CVE-2021-34721— Cisco IOS XR Software Command Injection Vulnerabilities
Quick assessment
Affected
Cisco Cisco IOS XR Software
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Cisco IOS XR是美国思科（Cisco）公司的一套为其网络设备开发的操作系统。 Cisco IOS XR 软件存在安全漏洞，该漏洞源于软件中的XML配置管理器对于用户提供的命令的输入验证不足，漏洞可能允许经过身份验证的本地攻击者注入任意命令，这些命令将通过该漏洞执行。攻击者可利用该漏洞可以通过对设备进行身份验证并向受影响的命令提交精心设计的输入来利用这个漏洞。成功的利用可以允许攻击者访问底层。
Possible ATT&CK Techniques 1 AI
T1068 · Exploitation for Privilege Escalation
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I. Basic Information for CVE-2021-34721
Vulnerability Information
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Vulnerability Title
Cisco IOS XR Software Command Injection Vulnerabilities
Source: CVE Program / CVE List V5
Vulnerability Description
Multiple vulnerabilities in the CLI of Cisco IOS XR Software could allow an authenticated, local attacker to gain access to the underlying root shell of an affected device and execute arbitrary commands with root privileges. For more information about these vulnerabilities, see the Details section of this advisory.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
OS命令中使用的特殊元素转义处理不恰当(OS命令注入)
Source: CVE Program / CVE List V5
Vulnerability Title
Cisco IOS XR 操作系统命令注入漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Cisco IOS XR是美国思科（Cisco）公司的一套为其网络设备开发的操作系统。 Cisco IOS XR 软件存在安全漏洞，该漏洞源于软件中的XML配置管理器对于用户提供的命令的输入验证不足，漏洞可能允许经过身份验证的本地攻击者注入任意命令，这些命令将通过该漏洞执行。攻击者可利用该漏洞可以通过对设备进行身份验证并向受影响的命令提交精心设计的输入来利用这个漏洞。成功的利用可以允许攻击者访问底层。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| Cisco | Cisco IOS XR Software | n/a | - |
|
II. Public POCs for CVE-2021-34721
| # | POC Description | Source Link | Shenlong Link |
|---|
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Vendor Advisories for CVE-2021-34721 (1)
-
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-cmd-inj-wbZKvPxc vendor-advisory x_refsource_CISCO
Same Patch Batch · Cisco · 2021-09-09 · 13 CVEs total
| CVE-2021-34720 | 8.6 HIGH | Cisco IOS XR Software IP Service Level Agreements and Two-Way Active Measurement Protocol |
| CVE-2021-34718 | 8.1 HIGH | Cisco IOS XR Software Arbitrary File Read and Write Vulnerability |
| CVE-2021-34728 | 7.8 HIGH | Cisco IOS XR Software Authenticated User Privilege Escalation Vulnerabilities |
| CVE-2021-34719 | 7.8 HIGH | Cisco IOS XR Software Authenticated User Privilege Escalation Vulnerabilities |
| CVE-2021-34713 | 7.4 HIGH | Cisco IOS XR Software for ASR 9000 Series Routers Denial of Service Vulnerability |
| CVE-2021-34722 | 6.7 MEDIUM | Cisco IOS XR Software Command Injection Vulnerabilities |
| CVE-2021-34786 | 6.5 MEDIUM | Cisco BroadWorks CommPilot Application Software Vulnerabilities |
| CVE-2021-34785 | 6.5 MEDIUM | Cisco BroadWorks CommPilot Application Software Vulnerabilities |
| CVE-2021-34709 | 6.0 MEDIUM | Cisco IOS XR Software for Cisco 8000 and Network Convergence System 540 Series Routers Ima |
| CVE-2021-34708 | 6.0 MEDIUM | Cisco IOS XR Software for Cisco 8000 and Network Convergence System 540 Series Routers Ima |
| CVE-2021-34737 | 5.8 MEDIUM | Cisco IOS XR Software DHCP Version 4 Server Denial of Service Vulnerability |
| CVE-2021-34771 | 5.5 MEDIUM | Cisco IOS XR Software Unauthorized Information Disclosure Vulnerability |
IV. Related Vulnerabilities
Same product: Cisco IOS XR Software
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Same vendor: Cisco
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V. Comments for CVE-2021-34721
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